Bump base64 from 0.12.1 to 0.12.2 (#613)
Bump base64 from 0.12.1 to 0.12.2 (#613)

Bumps [base64](https://github.com/marshallpierce/rust-base64) from 0.12.1 to 0.12.2.
- [Release notes](https://github.com/marshallpierce/rust-base64/releases)
- [Changelog](https://github.com/marshallpierce/rust-base64/blob/master/RELEASE-NOTES.md)
- [Commits](https://github.com/marshallpierce/rust-base64/compare/v0.12.1...v0.12.2)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
alex/ct-tools,alex/ct-tools